<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        #output{
            width: 200px;
            height: 200px;
        }
    </style>
</head>
<body>
        <input type="text" id="score">
        <input type="button" id="btn" value="评判">
        <div id="output"></div>


            <script>
                var scoreobj = document.getElementById('score');
                var btn = document.getElementById('btn');
                var output = document.getElementById('output');
                btn.onclick = function () {
                    var score = scoreobj.value;
                    var s =' ';

                    if(score==10){
                        s = '满分';
                    }
                    else{
                        if(score >=9 && score<10){
                            s = '优秀';
                        }
                       else {
                            if (score >=8 && score<9){
                                s = '良好';
                            }
                            else{
                                if (score >=7 && score<8){
                                    s = '一般';
                                }
                                else {
                                    if(score >=6 && score<7){
                                        s = '及格';
                                    }
                                    else {
                                        s = '不及格';
                                    }
                                }
                            }
                        }
                    }

                    console.log(s);


                    output.innerHTML = s;
                }
            </script>
</body>
</html>